为了弥补传统MPCA(Modular Principal Component Analysis)方法在人脸识别中忽略子图像之间差异的缺陷,本文提出了一种基于独立特征提取的MPCA方法(Modular PCA Based on Independent Feature,IFMPCA).首先选取人脸训练样本中具有相似...为了弥补传统MPCA(Modular Principal Component Analysis)方法在人脸识别中忽略子图像之间差异的缺陷,本文提出了一种基于独立特征提取的MPCA方法(Modular PCA Based on Independent Feature,IFMPCA).首先选取人脸训练样本中具有相似光照、表情和姿态的图像进行分块,然后将训练样本的子图像和测试样本的子图像进行最优投影,得到子特征矩阵.最后,求得样本间的距离,利用最小距离分类器进行样本的分类.在Yale人脸数据库上的实验结果表明:IFMPCA算法在人脸正确识别率方面优于传统PCA算法.展开更多
针对间歇生产过程存在的多阶段问题,提出了基于数据动态特性CPV(1)(cumulative percent variance of the first principal component)指标进行模糊聚类实现多阶段软划分的方法,解决了传统分段方式对间歇过程进行硬划分的缺陷,使得过程...针对间歇生产过程存在的多阶段问题,提出了基于数据动态特性CPV(1)(cumulative percent variance of the first principal component)指标进行模糊聚类实现多阶段软划分的方法,解决了传统分段方式对间歇过程进行硬划分的缺陷,使得过程多阶段划分更加准确。在此基础上建立多阶段具有时变主元协方差的改进MPCA(multiway principal component analysis)模型进行间歇过程的监视。将此方法应用于青霉素发酵过程,验证了该方法的可靠度和有效性。展开更多
Multi-way principal component analysis（MPCA）has received considerable attention and been widely used in process monitoring.A traditional MPCA algorithm unfolds multiple batches of historical data into a two-dimensio...Multi-way principal component analysis（MPCA）has received considerable attention and been widely used in process monitoring.A traditional MPCA algorithm unfolds multiple batches of historical data into a two-dimensional matrix and cut the matrix along the time axis to form subspaces.However,low efficiency of subspaces and difficult fault isolation are the common disadvantages for the principal component model.This paper presents a new subspace construction method based on kernel density estimation function that can effectively reduce the storage amount of the subspace information.The MPCA model and the knowledge base are built based on the new subspace.Then,fault detection and isolation with the squared prediction error（SPE）statistic and the Hotelling（T2）statistic are also realized in process monitoring.When a fault occurs,fault isolation based on the SPE statistic is achieved by residual contribution analysis of different variables.For fault isolation of subspace based on the T2 statistic,the relationship between the statistic indicator and state variables is constructed,and the constraint conditions are presented to check the validity of fault isolation.Then,to improve the robustness of fault isolation to unexpected disturbances,the statistic method is adopted to set the relation between single subspace and multiple subspaces to increase the corrective rate of fault isolation.Finally fault detection and isolation based on the improved MPCA is used to monitor the automatic shift control system（ASCS）to prove the correctness and effectiveness of the algorithm.The research proposes a new subspace construction method to reduce the required storage capacity and to prove the robustness of the principal component model,and sets the relationship between the state variables and fault detection indicators for fault isolation.展开更多
文摘为了弥补传统MPCA(Modular Principal Component Analysis)方法在人脸识别中忽略子图像之间差异的缺陷,本文提出了一种基于独立特征提取的MPCA方法(Modular PCA Based on Independent Feature,IFMPCA).首先选取人脸训练样本中具有相似光照、表情和姿态的图像进行分块,然后将训练样本的子图像和测试样本的子图像进行最优投影,得到子特征矩阵.最后,求得样本间的距离,利用最小距离分类器进行样本的分类.在Yale人脸数据库上的实验结果表明:IFMPCA算法在人脸正确识别率方面优于传统PCA算法.
文摘针对间歇生产过程存在的多阶段问题,提出了基于数据动态特性CPV(1)(cumulative percent variance of the first principal component)指标进行模糊聚类实现多阶段软划分的方法,解决了传统分段方式对间歇过程进行硬划分的缺陷,使得过程多阶段划分更加准确。在此基础上建立多阶段具有时变主元协方差的改进MPCA(multiway principal component analysis)模型进行间歇过程的监视。将此方法应用于青霉素发酵过程,验证了该方法的可靠度和有效性。
基金Supported by National Hi-tech Research and Development Program of China(863 Program,Grant No.2011AA11A223)
文摘Multi-way principal component analysis（MPCA）has received considerable attention and been widely used in process monitoring.A traditional MPCA algorithm unfolds multiple batches of historical data into a two-dimensional matrix and cut the matrix along the time axis to form subspaces.However,low efficiency of subspaces and difficult fault isolation are the common disadvantages for the principal component model.This paper presents a new subspace construction method based on kernel density estimation function that can effectively reduce the storage amount of the subspace information.The MPCA model and the knowledge base are built based on the new subspace.Then,fault detection and isolation with the squared prediction error（SPE）statistic and the Hotelling（T2）statistic are also realized in process monitoring.When a fault occurs,fault isolation based on the SPE statistic is achieved by residual contribution analysis of different variables.For fault isolation of subspace based on the T2 statistic,the relationship between the statistic indicator and state variables is constructed,and the constraint conditions are presented to check the validity of fault isolation.Then,to improve the robustness of fault isolation to unexpected disturbances,the statistic method is adopted to set the relation between single subspace and multiple subspaces to increase the corrective rate of fault isolation.Finally fault detection and isolation based on the improved MPCA is used to monitor the automatic shift control system（ASCS）to prove the correctness and effectiveness of the algorithm.The research proposes a new subspace construction method to reduce the required storage capacity and to prove the robustness of the principal component model,and sets the relationship between the state variables and fault detection indicators for fault isolation.
